Plating metals.



WILLIAM E. WATKINS, OF NEW YORK, N. Y.

PLATING METALS.

No Drawing.

To all whom it may concern:

Be it known that I, WILLIAM E. WATKINS, a citizen of the United States, residing in the city, county, and State of New York, have invented certain new and useful Improvements in Plating Metals; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

The present invention relates to the plating of one metal with another and particularly to the plating of articles (such as sheets) of iron or steel with copper or other metal of lower melting point than the metal to be plated.

The invention is based upon the discovery that the copper or other plating metal may be applied to the iron or steel sheet as finely divided metal, in connection with a suitable vehicle having for its purpose to obtain an appropriate distribution of the finely divided metal upon the sheet to be plated and to maintain such distribution until the finely divided metal, when subjected to a melting heat forms a non-stripping plating union with the sheet. WVhere the conditions of the operation are such that, unless protected from the oxidizing action of the gases in which the plating operation is being conducted, an effective plating would not be obtained, I may associate with the finely divided copper a reducing agent, (such as finely divided solid carbon), or in addition to or in substitution therefor a fluid or viscous hydrocarbon which may serve as the vehicle itself.

The finely divided metal appropriate to the uses of the invention may be obtained to advantage either by precipitating the metal from a salt thereof, or by reducingit in a pulverulent form from any appropriate reducible compound. So also, the protective reducing agent to be employed with the finely divided metal may, to advantage, be lamp-black or the like, obtained in any well known manner from the destructive distillation of a hydrocarbon, or may consist of finely ground carbon; or it may consist of a liquid or semi-liquid hydrocarbon, used either with or without the addition of the finely divided carbon, according to the exigencies of the case. When used alone, or in conjunction with finely divided carbon, the liquid or semi-liquid hydrocarbon employed Specification of Letters Patent.

Patented Sept. 12, 1916.

Application filed August 17, 1915. Serial No. 45,855.

will itself serve as a vehicle for the finely divided metal and, in fact, it is preferred to use a hydrocarbon as a vehicle, in most cases mainly because of its nbn-oxidizing characteristic, its spreading qualities, and (particularly when semi-liquid or viscous), the facility with which it holds the solid particles of the finely divided metal and finely divided carbon in suspension and substantially uniform distribution therein.

As an example of the practice of the invention, I may instance the plating with copper of iron sheets, of the kind employed in the manufacture of tin plate by the familiar dipping operation. Finely divided copper, preferably obtained by precipitation or reduction, is applied to the surface of the 1ron sheet together with any suitable liquid or semi-liquid vehicle. The vehicle employed may be water, or a light hydrocarbon (such as kerosene, or the like), but is preferably a semi-liquid or viscous hydrocarbon, such as a crude petroleum, say Mexican or Oklahoma crude petroleum, having an asphaltic base. In order to obtain a desirably uniform distribution of the finely divided copper through the vehicle, it is preferred to grind the mixture, and, when finely divided solid carbon is to be employed, to likewise grind in such finely divided carbon. The result of the grinding together of the vehicle and the finely divided consituents is to bring the entire mass to a consistency in which the finely divided constituents are held in suspension, and which will adapt itself readily to theuniform coating of'the iron sheets.

The amount of finely divided copper or other finely divided metal, will depend upon the desired thickness of the plating; and the amount of finely divided solid carbon, if any, to be employed, as well as the character and amount of the liquid or semi-liquid vehicle will depend upon the desired viscosity of the coating to permit it to be applied uniformly to the iron sheet, and also upon the protective effect required in any particular instance. In the plating of iron sheets with copper, I may, for instance, obtain a compact non-stripping plating layer of the copper covering the iron surface by applying to the iron sheet a uniform coating of the voscous, composition or paste of which the finely divided copper is a constituent, the copper being present in the proportion of say one part by weight of finely divided cop- 1 iron sheet or other article to be plated in a i ducing agent, or where it is low in reducing constituents (as, for instance, when it is a light hydrocarbon such as kerosene). The Mexican crude petroleum should preferably be of a specific gravity represented by a weight of 7% pounds to the gallon. As hereinbefore indicated, the function of the finely divided carbon is largely protection of the copper, and the reduction of any copper oxid that may be present in or upon the copper, and the proportionate amount employed will consequently vary somewhat with the exigencies of the operation.

The paste or suspension containing the finely divided copper is to be applied to the coating of uniform depth and consistency, and preferably by means of rolls which spread an even, dense, and compact layer upon both surfaces of the sheet. As the coated sheet emerges from the rolls, it is introduced into a suitable furnace and is subjected therein to a temperature of say 2000 F. or thereabout, sufiicient in degree and duration to cause the copper to form a non-stripping plating upon the surfaces of the sheet. In those instances where the furnace conditions bring about an oxidation of the iron, the copper-coated sheet will be found to have a superficial layer of iron oxid, but this may readily be removed, by abrasion, pickling, or any other suitable means.

What I claim is:

1. The process of plating one metal with another, which comprises the following steps: forming a substantially homogeneous metal-plating suspension, comprising finely divided particles of the plating metal together with a suitable spreading vehicle containing in suspension a finely divided reducing agent; applying said suspension in an even coating layer upon the metal to be plated; and subjecting the metal to be plated, together with the coating thereon, to heat, the quantity of said coating and the intensity and duration of the heat being sufficient to form a plating layer of the plating metal adherent to the metal to be plated.

2. The process of plating one metal with another, which comprises the following steps: forming a substantially homogeneous metal-plating suspension, comprising finely divided particles of plating metal together with a suitable spreading vehicle of a reducing character; applying said suspension in an even coating layer upon the metaLto be plated; and subjecting the metal to be plated, together with the coating thereon, to heat, the quantity of said coating and the intensity and duration of the heat being suflicient to form a plating layer of the plating metal adherent to the metal to be plated.

3. The process of plating one metal with another, which comprises the following steps: forming a substantially homogeneous metal-plating suspension, comprising finely divided particles of the plating metal to gether with a suitable spreading vehicle, containing, in suspension, finely divided carbon; applying said suspension in an even coating layer upon the metal to be plated; and subjecting the metal to be plated, together with the coating thereon, to heat, the quantity of said coating and the intensity and duration of the heat being sufficient to form a plating layer of the plating metal adherent to the metal to be plated.

4. The process of plating one metal with another, which comprises the following steps: forming a substantially homogeneous metal-plating suspension, comprising finely divided particles of the plating metal together with a suitable spreading vehicle of a reducing character, containing, in suspension, finely divided carbon; applying said suspension in an even coating layer upon the metal to be plated; and subjecting the metal to be plated, together with the coating thereon, to heat, the quantity of said coating and the intensity and duration of the heat being sufiicient to form a plating layer of the plating metal adherent to the metal to be plated.

5. The process of plating iron or steel with copper, which comprises the following steps: forming a substantially homogeneous copper plating suspension, comprising finely divided particles of copper together with. a'

suitable spreading vehicle; applying said suspension in an even coating layer upon the metal to be plated; and subjecting the metal to be plated, together with the coating thereon, to heat, the quantity of said coating and the intensity and duration of the heat being suflicient to form a plating layer of copper adherent to the metal to be plated.

6. The process of plating iron or steel with copper, which comprises the following steps: forming a substantially homogeneous copper plating suspension, comprising finely divided particles of copper together with a suitable spreading vehicle of a reducing character; applying said suspension-in an even coating layer upon the metal to be plated; and subjecting the metal to be plated, together with the coating thereon, to heat, the quantity of said coating and the intensity and duration of the heat being suflicient to form a plating layer of copper adherent to the metal to be plated.

7. The process of plating iron or steel with copper which comprises the following steps: forming a substantially homogeneous copper plating suspension, comprising finely divided particles of copper together with a suitable spreading vehicle, containing, in suspension, finely divided carbon; applying said suspension" in an even coating layer upon the metal to be plated; and subjecting the metal to be plated, together with the coating thereon, to heat, the quantity of said coating and the intensity and duration of the heat being sufficient to form a plating layer of copper adherent to the metal to be plated.

8. The process of plating iron or steel with copper, which comprises the following steps: forming a substantially homogeneous copper plating suspension, comprising finely divided particles of copper together with a suitable spreading vehicle of a reducing character, containing, in-suspension, finely divided carbon; applying said suspension in an even coating layer upon the metal to be plated; and subjecting the metal to be plated, together with the coating thereon, to heat, the quantity of said coating and the intensity and duration of the heat being sufficient to form a plating layer of copper adherent to the metal to be plated.

In testimony whereof I affix my signa-' ture.

WILLIAM E. WATKINS. 

